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MiniMental
01-08-2023, 08:26 PM
Yo,

Had a customers 2004 2.4 Cabriolet BDV engine in for a cooling hose replacement today, which meant inlet manifold etc off to reach it.

On finishing the job, the ABS light popped up when running the car.


P01435 - Brake Pressure Switch failure

Measuring blocks in VCDS read 296Bar constantly.

Am I right in thinking this is the switch that’s screwed into the side of the pump next to the coolant reservoir? The reading doesn’t change if I unplug it or press the pedal.

Could anything I’ve touched while removing inlet etc cause this? I’m struggling to figure out why it’s suddenly appeared.

Seems very odd but needs rectifying quickly. Reluctant to order a £130 switch if it’s likely to be something else.

Cheers for any insight.

Aidan

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Crasher
02-08-2023, 10:05 AM
8E0 907 597 £366.60 genuine, approx £130 aftermarket if you can get one. There are two sub versions of the code, basic settings or electrical fault. This is the sort of crap you have to endure working on old cars, just because something fails when you have the car in doesn't mean it is your fault. Some people think that when their car goes in for work it has some sort of blanket warranty against new faults.

https://imageproxy.ifunny.co/crop:x-20,resize:640x,quality:90x75/images/99b431af8ce6c64cbd58f8eb1318a8fe5d4f747dd660dae4e2 f6e340f31752d0_1.jpg

MiniMental
16-08-2023, 07:47 PM
8E0 907 597 £366.60 genuine, approx £130 aftermarket if you can get one. There are two sub versions of the code, basic settings or electrical fault. This is the sort of crap you have to endure working on old cars, just because something fails when you have the car in doesn't mean it is your fault. Some people think that when their car goes in for work it has some sort of blanket warranty against new faults.

https://imageproxy.ifunny.co/crop:x-20,resize:640x,quality:90x75/images/99b431af8ce6c64cbd58f8eb1318a8fe5d4f747dd660dae4e2 f6e340f31752d0_1.jpg

Thanks for the reply matey.

Update.

I’ve tried a different working switch on and it’s still present with the same fault. Fine for a few minutes then fault comes up. If you watch the pressure on live data, it’s randomly showing whatever it feels like, unless I unplug the switch in which case it shows 296Bar permanently.

Am I right in thinking this would be the ABS unit electronics at fault and not the switch? If so, I suspect it’s beyond my capability to rectify at this point.

From memory, replacing abs unit is quite involved.


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Crasher
17-08-2023, 07:33 PM
Impossible to say remotely

MiniMental
02-10-2023, 11:20 PM
Turns out it was the abs unit itself. Had it fixed by ECU Testing [emoji108][emoji108]

Now I’ve got these to contend with before it can go back to its owner. Joy. Haha.

https://uploads.tapatalk-cdn.com/20231002/d8bf0e26076b2800cc14f3e3c3ded058.jpg
https://uploads.tapatalk-cdn.com/20231002/2f0e708f55c6231f4aae439ade226097.jpg
https://uploads.tapatalk-cdn.com/20231002/a96ee1ed86b6654cad8bae8a83fc8242.jpg
https://uploads.tapatalk-cdn.com/20231002/bf3e0ce9a6faabab832555c0a3bc43c3.jpg


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